Opening: Light in all its nuances is the essence of photography, from sun-bleached mornings to twilight's last gleam. For its new exhibition opening today, the Mpls Photo Center put out a call for images taken in the hours of light's absence. Elaborately titled "Early Morning After Dark: From Dusk's Last to Dawn's First Light," the show follows a format used successfully before by the center, picking more than 100 images out of dozens of applicants from all over the world. Pictorial and dramatic, the scenes range from brightly lit urban parking lots to starry wilderness skies and period motels like "Canyon" by Josh Grubbs.